QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Footnotes) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended			36 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019
Schedule of Quarterly Financial Information [Line Items]
Net income from continuing operations attributable to noncontrolling interests									$ (50)	$ (292)	$ (274)
Production and delivery									11,514	11,687	10,258
Interest expense, net									(620)	(945)	(801)
Metals inventory adjustments	$ 79	$ 41	$ 59						179	4	8
Net Income (Loss) From Continuing Operations, Inventory Write-down									$ 144
Net Income (Loss) From Continuing Operations, Inventory Write-Down, Per Share									$ 0.10
Environmental obligations and shutdown costs		19		$ 35					$ 68
Net gain on sales of assets					$ 82	$ 70	$ 45	$ 11	417	$ 208	81
Gain (Loss) on Disposition of Assets, Common Shareholder									$ (339)
Net gains on sales of assets (usd per share)									$ 0.23	$ 0.14
Income Tax Credits and Adjustments										$ 632
Income Tax Credits and Adjustments, Net of Noncontrolling Interest										$ 574
Earnings per share attributable to common stockholders related to Tax Reform (usd per share)										$ 0.39
Change in PT-FI tax rates									$ 0	$ 504	0
Tax Cuts and Jobs Act of 2017, provisional income tax expense (benefit)									0	123	393
Operating income (loss)	(775)	38	(33)	$ (321)	(316)	$ (1,315)	(1,664)	$ (1,459)	(1,091)	(4,754)	(3,690)
Extinguishment of Debt, Gain (Loss), Net of Tax									$ 26
Extinguishment of Debt, Gain (Loss), Per Share, Net of Tax									$ 0.02
Freeport Cobalt
Schedule of Quarterly Financial Information [Line Items]
Depreciation Expense on Reclassified Assets					(48)					(31)
PT Freeport Indonesia [Member]
Schedule of Quarterly Financial Information [Line Items]
Change in PT-FI tax rates									$ 0	504	0
Production and Delivery Costs [Member]
Schedule of Quarterly Financial Information [Line Items]
Environmental obligations and shutdown costs		15
Operating Expense [Member] | Freeport Cobalt
Schedule of Quarterly Financial Information [Line Items]
Net income from continuing operations attributable to noncontrolling interests										$ (30)
Continuing operations (in dollars per share)										$ 0.02
Operating income (loss)										$ 50
Cerro Verde
Schedule of Quarterly Financial Information [Line Items]
Loss Contingency, Loss in Period									16
PT-FI charges [Member] | PT Freeport Indonesia [Member]
Schedule of Quarterly Financial Information [Line Items]
Loss Contingency, Loss in Period	266								460	223
Loss contingency, loss In period, attributable to parent									$ 379	$ 110
Gain (loss) in period, per share (in dollars per share)									$ (0.26)	$ (0.08)
Inventory Adjustment					43		$ 12
PT-FI charges [Member] | Interest expense | PT Freeport Indonesia [Member]
Schedule of Quarterly Financial Information [Line Items]
Loss Contingency, Loss in Period	$ 78
PT-FI charges [Member] | Other Expense [Member] | PT Freeport Indonesia [Member]
Schedule of Quarterly Financial Information [Line Items]
Net income from continuing operations attributable to noncontrolling interests									$ 188
PT-FI charges [Member] | Sales [Member] | PT Freeport Indonesia [Member]
Schedule of Quarterly Financial Information [Line Items]
Net income from continuing operations attributable to noncontrolling interests		$ 166
PT-FI charges [Member] | Production and Delivery Costs [Member] | PT Freeport Indonesia [Member]
Schedule of Quarterly Financial Information [Line Items]
Net income from continuing operations attributable to noncontrolling interests			$ 28
Loss Contingency, Offer to Other Party					69
Permit Fees					32
Payroll withholding taxes					72					$ 72
Cerro Verde Royalty Dispute | Royalty Assessments | Cerro Verde
Schedule of Quarterly Financial Information [Line Items]
Loss contingency, loss In period, attributable to parent									7	$ 195	186	$ 388
Gain (loss) in period, per share (in dollars per share)										$ (0.13)
Net income from continuing operations attributable to noncontrolling interests									7	$ 176	169	352
Production and delivery									6	14	203	223
Interest expense, net									(10)	(370)	(145)	(525)
Other expense									$ 0	(22)	0	$ (22)
Minimum Tax Credit Carryforwards [Member] | PT Freeport Indonesia [Member]
Schedule of Quarterly Financial Information [Line Items]
Change in PT-FI tax rates										549
MOEF Framework
Schedule of Quarterly Financial Information [Line Items]
Permit Fees										$ 32
Site Remediation, Reclamation and Closure Costs
Schedule of Quarterly Financial Information [Line Items]
Continuing operations (in dollars per share)									$ 0.05	$ 0.04
Environmental obligations and shutdown costs										$ 57
Indonesia
Schedule of Quarterly Financial Information [Line Items]
Cost of Goods and Services Sold					$ 62
Operating Segments | South America
Schedule of Quarterly Financial Information [Line Items]
Production and delivery									$ 2,326	2,365	2,244
Interest expense, net									(114)	(429)	(212)
Metals inventory adjustments									2	0	0
Net gain on sales of assets									0	0	0
Operating income (loss)									(578)	(735)	(916)
Operating Segments | South America | Cerro Verde
Schedule of Quarterly Financial Information [Line Items]
Production and delivery									1,852	1,887	1,878
Interest expense, net									(114)	(429)	(212)
Metals inventory adjustments									2	0	0
Net gain on sales of assets									0	0	0
Operating income (loss)									(621)	(709)	(868)
Operating Segments | Indonesia | Grasberg Segment [Member]
Schedule of Quarterly Financial Information [Line Items]
Loss Contingency, Loss in Period										223
Production and delivery									2,055	1,864	1,735
Interest expense, net									(82)	(1)	(4)
Metals inventory adjustments									5	0	0
Net gain on sales of assets									0	0	0
Operating income (loss)									$ (180)	(2,966)	$ (2,028)
Tax Authority, In Papau, Indonesia
Schedule of Quarterly Financial Information [Line Items]
Change in PT-FI tax rates										(504)
Tax Authority, In Papau, Indonesia | PT Freeport Indonesia [Member]
Schedule of Quarterly Financial Information [Line Items]
Change in PT-FI tax rates										$ (482)
Cerro Verde Collective Labor Agreement [Member] | Operating Segments | South America | Cerro Verde
Schedule of Quarterly Financial Information [Line Items]
Continuing operations (in dollars per share)										$ 0.02
Production and delivery										$ (69)
Cost of Goods Sold, Excluding Depreciation, Depletion and Amortization, Net of Noncontrolling Interest										(22)
Cost of Goods and Services Sold										$ 69